Berzerk is a multi-directional shooter video arcade game, released in 1980 by Stern Electronics of Chicago.

The player controls a green stick man. Using a joystick and a firing button that activates a laser-like weapon, the player navigates a simple maze filled with many robots, who fire lasers back at the player character. A player can be killed by being shot, by running into a robot or an exploding robot, coming into contact with the electrified walls of the maze itself, or by being touched by the player's nemesis, Evil Otto.

The function of Evil Otto, represented by a bouncing smiley face, is to quicken the pace of the game. Otto is unusual, with regard to games of the period, in that there is no way to kill him. Otto can go through walls with impunity and is attracted to the player character. If robots remain in the maze Otto moves slowly, about half as fast as the humanoid, but he speeds up to match the humanoid's speed once all the robots are killed. Evil Otto moves exactly the same speed as the player going left and right but he can move faster than the player going up and down; thus, no matter how close Otto is, the player can escape as long as they can avoid moving straight up or down.

The player advances by escaping from the maze through an opening in the far wall. Each robot destroyed is worth 50 points. Ideally, all the robots in the current maze have been destroyed before the player escapes, thus gaining the player a per-maze bonus (ten points per robot). The game has 65,536 rooms (256x256 grid), but due to limitations of the random number generation there are fewer than 1024 maze layouts (876 unique).

Alan McNeil, an employee of Universal Research Laboratories (a division of Stern Electronics), had a dream one night involving a black-and-white video game in which he had to fight robots. This dream, with heavy borrowing from the BASIC game Robots (Daleks in the UK), was the basis for Berzerk, which was named for Fred Saberhagen's Berserker series of science fiction novels.

"Evil Otto" was named after Dave Otto, security chief at McNeil's former employer Dave Nutting Associates. According to McNeil, Otto would, "[smile] while he chewed you out." He would also lock McNeil and his fellow employees out of the building to enforce a noon-hour lunch, as well as piping "beautiful" music into every room.

The idea for a black-and-white game was abandoned when the color game Defender was released earlier the same year to significant success. At that point Stern decided to use a color overlay board for Berzerk. A quick conversion was made, and all but the earliest versions of the game shipped with a color CRT display. The game was test-marketed successfully at a Chicago singles bar before general release.

1 Player Start                             1

2 Player Start                             2

Coin 1                                     5

Coin 2                                     6

Coin 3					   7

Free Game (not logged in bookkeeping)      8

Bookkeeping				  F1

P1 Up                                     UP

P1 Down                                 DOWN

P1 Left                                 LEFT

P1 Right                               RIGHT

P1 Button 1             LCONTROL or Mouse B1

P2 Up                                      R

P2 Down                                    F

P2 Left                                    D

P2 Right                                   G

P2 Button 1                                A